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From: Eli Zaretskii <eliz@gnu.org>
Newsgroups: gmane.emacs.devel
Subject: Re: Using __builtin_expect (likely/unlikely macros)
Date: Tue, 16 Apr 2019 05:34:54 +0300
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To: Alex Gramiak <agrambot@gmail.com>
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> From: Alex Gramiak <agrambot@gmail.com>
> Date: Mon, 15 Apr 2019 18:16:02 -0600
> Cc: emacs-devel@gnu.org
> 
> To human readers, yes, but from what I can tell, GCC is mixed on this.
> When applying the following diff that surrounds emacs_abort in
> bytecode.c and xdisp.c, the assembly in both applied/unapplied is the
> same for bytecode.c, but not for xdisp.c (even without the LIKELY
> cases). I tested using gcc -O2 -S.

I'm not sure whether you put LIKELY and UNLIKELY somewhat randomly,
just for testing, or did you really think each place is
likely/unlikely as in the change, but at least some places in xdisp.c
are wrong: they use LIKELY where UNLIKELY is more appropriate, abd
vice versa.